Transfer feed press



Feb. 18, 1969 H r, BURKE ETAL TRANSFER FEED PRESS Sheet Filed Feb. 24, 1967 BWLL zmprwm JJM O 08 NOE m gim7 INVENTORS HARRY T. BURKE RALPH L.ANDREWS r w W 1969 H. T. BURKE ETAL 3,

TRANSFER FEED PRESS Filed Feb. 24, 1967 FIG. 6 INVENTORS k HARRY T. BURKE 38 RALPH L. ANDREWS ATTORNEYS..

United States Patent Office 3,428,166 Patented Feb. 18, 1969 3,428,166 TRANSFER FEED PRESS Harry T. Burke and Ralph Lowye Andrews, Hastings, Mich., assignors to E. W. Bliss Company, Canton, Ohio, a corporation of Delaware Filed Feb. 24, 1967, Ser. No. 618,427 US. Cl. 198-218 Int. Cl. B65g 25/04 4 Claims ABSTRACT OF THE DISCLOSURE T he invention will he described with particular reference to a transfer feed press having a transfer feed mechanism in which a plurality of pairs of lingers hold a part for the purpose of transferring it successively from a receiving station to a plurality of die stations, one after the other, and then to a discharge station; however, it will be appreciated that this paricular application of the invention is merely for the purpose of illustration and that, by and large, the invention has a great many applications particularly where high speed material handling and precision positioning of a part are required.

Heretofore trans-fer feed mechanisms have been arranged to move pairs of fingers toward and away from each other for intermittent gripping of a part. Also, they have generally a forward and return motion for longitudinal feed of the part from station to station. Rotary cams disposed at one end of the transfer feed mechanism are employed to impart a reciprocatory longitudinal move ment to a slide carrying the transfer feed lingers and an oscillatory, close and separate movement to the lingers in timed relationship. A transfer feed mechanism of this type is disclosed in US. Patent 1,426,039, issued \Aug. '15, 1922.

A principal disadvantage of such transfer feed mechanisms has been the inability to time the separate drives with suflicient precision for high speed press operation. Also, since constant and repeated change of direction is required, the drives consume too much energy in the form of heavy links, levers, bell cranks and the like, which have a great many turning points that incur frictional losses prohibiting high speed operation.

Moreover, in such prior art drives separate timing for close coordinated action of the drives has not been known heretofore which lack of flexibility and adjustment has impeded the use of such drives in high speed presses.

fl hese and other difliculties are overcome in the present invention which provides a transfer feed mechanism having continuous rotary drives having a much lower moment of inertia thus facilitating higher speed operation and, in addition, completely separate rotary-torotary/oscillatory drives capable of separate timing adjustments for close coordinated action.

In accordance with the invention there is provided a transfer feed and drive comp-rising a plurality of pairs of transfer feed fingers adapted to hold a part when in motion from one station to the next. A timing mechanism provides coordinated and timed movement of the drives to close the lingers on a part, transfer it to a station, separate them from the part, and return the rfingers to the initial station for receiving another part. \The driver includes separate rotary to rotary/oscillatory cam units connected at opposite ends of the transfer feed to impart longitudinal reciprocatory feed and lateral separate and close motion respectively, each cam unit being driven from a common shaft by means of separate adjustable drives each of which is capable of varying the periodic sequence of the respective motions.

it is the principal object of the invention to provide a transfer feed mechanism and drive for a high speed transfer feed press in which the drive means uses rotary motion as far as possible to effect reciprocatory and transverse movement. I

It is a further object of the invention that separate drives be employed for each movement.

Still another object is that each drive incorporates rotary-to-rotary/oscillatory cam units for each drive motion required so that the drives may be separately timed with a high degree of precision for higher speed operation.

r'Ihese and other objects and advantages will become more fully apparent by referring to the following description and drawings wherein:

FIGURE 1 is a partial top view of the transfer feed mechanism with a separate drive shown connected at opposite ends;

FIGURE 2. is a partial cross sectional view taken along line 22 of FIGURE 1:

FIGURE 3 is -a partial front view of the left side of a transfer feed press showing the drive for the separate and close transverse motion of the transfer feed mechanism;

FIGURE 4 is a side elevational view of the transfer feed press and drive of FIGURE 3;

FIGURE 5 is a partial front view of the right side of the same transfer feed press the clutch housing of which is shown broken away to illustrate the drive for the reciprocatory longitudinal feed motion of the transfer feed mechanism;

FIGURE 6 is -a partial side elevational view of the press and drive shown in FIGURE 5; and

FIGURE 7 is a time/displacement diagram showing the timing relationship of the separate drives.

Referring now to the drawings wherein the showings are for the purpose of illustrating a preferred embodiment of the invention only and not for the purpose of limiting same, FIGURES l and -2 show a transfer feed mechanism. for use with a transfer feed press in which a part is to be fed through the successive work stages of the press while being held by pairs of transfer feed fingers 12. The fingers 12 can move toward and away from each other to close on and separate from the part by virtue of a rotary-to-rotary/oscillatory.drive 13 at the left of the transfer feed mechanism and also move forward and return in a reciprocatory feed motion for transferring the part from one station to the next by virtue of a separate rot-ary-to-rotary/oscillatory drive 14 on the right as viewed in FIG- URE 1.

In more detail, the pairs of transfer feed fingers 12 are attached to a pair of slides 15, each of which is connected to a pair of coaxial shafts 16 extending parallel to each other on opposite sides of the transfer feed mechanism. Each outer shaft 17 of each pair of shafts 16 is connected at the right end to a yoke 18 which has a connector 19 for a connecting rod 20 of the drive 14. Thus each outer shaft 17 through the drive 14, connecting rod 20, and yoke 18 will reciprocate slides 15 and thus the pairs of transfer feed fingers 12.

Square shafts 21 are gibbed inside each shaft 17 and connected at the left of the transfer feed mechanism to cranks 22, connecting rods 23 and crank 24 of the sep arate drive 13. Thus, the movement of drive 13' is imarted through crank 24, connecting rods 23 and cranks 22, to each square shaft 21. The shafts 17 reciprocate in unison while the shafts 21 oscillate in unison, but counter to each other, which through their gibbed connection with the reciprocatory shafts 17 cause the latter to also oscillate during the separate and close period of the feed. A plurality of connector rods 25 are journaled in swivel bearings 28 in each slide 15 and transmit both the reciprocatory feed motion of shafts 17 and rotary oscillatory close and separate motion of the square shafts 21 to the pairs of transfer feed fingers 12 which due to the bearings 28, is imparted as straight line rectilinear longitudinal and transverse motion.

Referring now to the other figures, portions of a transfer feed press are shown in which the transfer feed mechanism is used. In FIGURES 3 and 4, the drive 13 is shown for imparting the separate and close movement to the pairs of transfer feed fingers 12 and in FIG- URES 5 and 6 the drive 14 for causing the reciprocatory feed motion is shown. In FIGURES 3-4 the left front and left side of the press are partially shown having a frame 30 in which is journaled a press crankshaft 32 carrying a flywheel 34. An angularly adjustable timing pulley 35 is keyed on the end of the crankshaft 32 for driving a timing belt 37 which is sheaved on a driven pulley 38 keyed to a shaft 40 of a rotary-to-rotary/oscillatory cam unit 42. The cam unit 42 is of the type more commonly referred to as a Ferguson drive which employs cams and gears in combination so as to receive continuous rotary motion at shaft 40 and deliver, not continuously but in a periodic manner, rotary/oscillatory motion at shaft 43 to which is keyed the crank 24. As will be described in more detail in connection with the reciprocatory feed drive 14, an outer ring 45 of the timing pulley 35 may be angularly adjusted by loosening bolts 47 and turning the ring 45 relative to an inner ring 49 keyed to the crankshaft 32 thus changing the periodicity of the rotaryto-rotary/ oscillatory cam unit 42.

In FIGURES 5 and 6 the right front and right side of the press are partially shown in which the frame 30 supports a clutch 50 mounted on the opposite end of the crankshaft 32 from the flywheel 34. Also mounted on the opposite extreme end of the crankshaft 32 is a second timing pulley 35', the parts of which are similar to the timing pulley 35 and will be identified by the same numerals with the addition of a prime mark. The timing pulley 35 also carries a timing belt 37 which is received on a driven pulley 38' keyed to the input 40' of a sep arate rotary-to-rotary/oscillatory cam unit 42' similar to the cam unit 42 for converting continuous rotational motion to periodic rotary/oscillatory motion, which motion is imparted through output shaft 43' and crank 44 to the connecting rod 20 for causing the reciprocatory feed motion of the transfer feed mechanism 10. As seen in FIGURE 5, in the broken section of the timing pulley 35, a set of bolts 47' may be loosened permitting the outer ring 45' to be angularly adjusted relative to the inner ring 49' which is keyed to the crankshaft 32 thus changing the essential periodicity of the cam unit 42 independently of the cam unit 42.

To determine the feed timing and coordinate the separate drives 13, 14, the timing pulleys 35, 35' are adjusted at the start which in effect displaces to the right or left the curves a, b, shown in the time displacement diagram of FIGURE 7. The upper curve a represents the reciprocatory feed motion imparted to the transfer feed mechanism by the drive 14 while the lower curve b represents the separate and close motion imparted to the transfer feed mechanism by the drive 13. When the essential periodicity required for the feed of a particular part has been determined, it will be assumed that the part is initially gripped by a pair of transfer feed fingers 12 and is moved forward to the next station by the drive 14 which according to curve a requires a cam displacement of approximately 120 while, as shown on curve b, the transfer feed fingers remain closed holding the part since the cam unit 42 is idle during a cam dwell period of the same duration. At the end of the dwell period, the cam unit 42 of the transverse drive 13 is brought into operation causing the separation of the pairs of transfer feed fingers 12 during a 60 cam displacement period while the reciprocatory feed, as shown in curve a, undergoes a dwell. The part has now been released at the next station.

Return movement of the transfer feed mechanism by drive 14 is shown by curve a while the drive 13 undergoes a dwell period as shown by curve b. Finally, shifting back to drive 13 the cam unit 42 controls the closing movement during a 60 cam displacement period as shown by curve b which closes the pairs of transfer feed fingers 12 on a second part while the cam unit 42'is in a 60 dwell period.

Having now described a preferred embodiment of the invention, it will be appreciated that various modifications may be made to the transfer feed mechanism and drive without departing from the invention as defined in the appended claims.

Having thus described our invention, we claim:

1. A transfer feed providing longitudinal feed and transverse clamping of a part while in motion from one station to the next comprising:

a pair of longitudinally extending slide members movable in a common plane reciprocally in a longitudinal feed direction and transversely toward and away from each other in a lateral clamping direction,

finger means on each slide member cooperating in pairs to clamp a part at a receiving station, longitudinally feed it to a next station, laterally separate from the part releasing it at the station, and return longitudinally to the receiving station,

a pair of coaxial shafts each extending parallel to the other on opposite sides of the slide members, said shafts being keyed to rotate together, the outer shafts being slidable longitudinally with respect to the inner shafts and connected to said slide members,

separate rotary-to-rotary/ oscillatory drive means connected to said pairs of coaxial shafts at the opposite ends thereof, one to impart reciprocal longitudinal feed motion and the other lateral separate and close clamping motion to each slide member, each said drive means being driven from a common shaft,

each outer shaft of each pair of shafts being connected at one end to the drive means which imparts reciprocal longitudinal feed motion to said slide members and each inner shaft being reciprocally received within each outer shaft and connected at the opposite end of the transfer feed to said other drive means for imparting transverse separate and close clamping motion to said slide members, and

timing means separately angularly adjustable to individually vary the periodicity of said separate drive means.

2. A transfer feed as set forth in claim 1 wherein said common shaft for driving the separate drive means is the crankshaft of a press, said crankshaft having mounted thereon said timing means to separately control the timing of said drive means including a pair of timing pulleys mounted on opposite ends of said crankshaft,

a pair of cam units mounted at the opposite ends of said transfer feed including a continuous rotary input drive and a rotary oscillatory output drive.

a timing belt extending from each timing pulley to the input drive of an associated cam unit,

connector means from the output drive of each cam unit to impart reciprocal longitudinal feed motion from one, and transverse clamping motion from the other, respectively to said outer and inner pairs of coaxial shafts, and

each said timing pulley being capable of angular adjustment relative to said crankshaft and input drive to vary the periodic relationship of said drive means.

3. A transfer feed according to claim 2 in which the connector means between the output drive of said one cam unit for transverse clamping motion and said inner pair of shafts comprises:

a pair of connecting rods,

a crank member connected to said output drive to which both connecting rods are attached at one end, and

a pair of cranks connected at the end of each inner shaft and to which a connecting rod of said pair is attached at the other end whereby the rotary oscillatory movement of said output drive is imparted in unison to said pair of inner shafts as counter rotary oscillatory movement and said connector means from the output drive of the other outer shafts including a connecting rod,

a crank connected to said output drive to which the connecting rod is attached at one end, and

yoke means connecting each of said outer shafts to the other end of said connecting rod.

4. A transfer feed according to claim 3 in which each said timing pulley comprises:

an outer ring over which is sheaved said timing belt,

an inner ring keyed to said crankshaft, and

fastener means for releasable coupling said outer ring relative to said inner ring and securing said rings in fixed angular relationship after adjustment.

References Cited UNITED STATES PATENTS 10/1962 Davies 198218 RICHARD E. AEGERTER, Primary Examiner. 

